Brake pad assmbly and method for collecting brake particles

ABSTRACT

A disk brake pad comprising a supporting base with which a layer of friction material is associated, characterized in that a wall of said supporting base having associated therewith the layer of friction material is passed through by at least one channel communicating with a chamber, defined in correspondence of the supporting base, for collecting the powders produced due to the wear of the friction material.

The present application is a continuation of application Ser. No.13/236,850, filed Sep. 20, 2011, the disclosure of which is herebyincorporated by reference herein in its entirety.

TECHNICAL FIELD

The present invention relates to a disk brake pad.

More precisely, the invention relates to a disk brake pad or assembly ofthe kind equipped with means for collecting the powders produced due tothe wear of the friction material, aiming therefore at reducing theprimary pollution caused by the dispersion of such powders into theenvironment.

PRIOR ART

Disk brake pads are commonly used in vehicles of any kind, in particularmotor vehicles, such as motor cars, motorcycles, railroad vehicles andso on.

As known, brake pads comprise a supporting base to which a layer offriction material adheres. The layer of friction material generates afriction on the brake disk when the material is pressed against the diskdue to a push, generally obtained by hydraulic pistons, against thesupporting base. In the past, the friction material mainly consisted ofa mixture of several materials where asbestos was prevailing. At presenthowever use of such material is prohibited and this kind of mixture isnowadays mostly replaced by mixtures mainly comprising binding resins,metals, abrasives and lubricants.

Analyses carried out on the powders produced due to the wear of thecurrently used friction material reveal the presence of metalsubstances, such as zinc, copper, barium, aluminum, magnesium, iron,calcium, potassium, sulphur, silicon and sodium, many of which, asknown, are noxious to living beings.

The problem of how to reduce dispersion into the environment of powdersproduced due to the wear of the friction material of the brake pads is ahighly topical subject and is of paramount importance for human health.

Analyses carried out on said powders reveal the presence of severalmetals and substances which are noxious especially in case ofinhalation.

Therefore several solutions have been developed in the past in anattempt to remedy the above problem.

A first group of solutions, such as for instance the ones disclosed inEP1256739, DE102005006465 and WO8102690, exploit the phenomenon of themagnetic attraction of metal particles in order to avoid powderdispersion into the environment.

More complex solutions, such as for instance the one disclosed inDE4240873, associate the brake assembly with an independent sucking unitequipped with ducts and a collecting reservoir.

Other solutions, such as for instance the one disclosed in U.S.2007/0000740, associate the brake assembly with a collecting device thatmechanically captures the powder produced due to the wear of the pads.

In other cases, solutions have been adopted according to which the brakepad itself is equipped with powder capturing means. An example of abrake pad of the above kind is disclosed in JP 11311272.

The solution disclosed in the latter document is however unsuitable,since it provides for collecting the powder through a bead of a materialarranged around the friction material, which bead consequently wearsduring use of the pad and moreover is not capable of retaining the greatamount of powder produced upon a prolonged use.

The other prior art solutions have not proved practically feasible andsufficiently effective in order to avoid powder dispersion, and moreoverthey proved to be expensive and complex to manufacture so that, in theabsence of a rule compelling to install them, they have not beencommercially successful. Moreover, such solutions generally have thedrawback that they do not allow removal of the collected powder, or theymake such removal difficult, in particular before the brake pad needs tobe replaced, with the result that the collecting effect of the prior artdevices is often made fruitless after a low mileage, for example due tothe non-removal of the accumulated powder.

It is a main object of the present invention to provide an alternativeor improved solution to the problem of how to avoid dispersion of thepowders produced due to the wear of the friction material of the diskbrake pads, with the main purpose of reducing the primary pollutioncaused by the dispersion of such powders into the environment.

It is another object of the present invention to provide a solution tothe above problem of pollution of the environment by brake powder, whichsolution moreover allows effectively collecting the powders produced dueto the wear of the friction material in order to allow the disposal andpossibly the recycling of the same powders, for instance formanufacturing new brake pads.

It is a further, but not the last object of the invention to provide abrake pad that can be industrialized with limited costs and thattherefore is suitable for large scale manufacturing at reasonable cost,for example with costs that are comparable to or at most little higherthan the costs of conventional brake pads.

DESCRIPTION OF THE INVENTION

At least one of the above and other objects is achieved through a diskbrake pad as claimed in the appended claims or disclosed in thisdescription.

A brake pad according to the invention in an embodiment can mainlydiffer from conventional pads in that it has a hollow supporting baseprovided with at least one channel communicating with the surface of thesupporting base with which the layer of friction material is associated,said channel being also arranged to pass through the friction materialwhen the channel is provided in correspondence of the portion of saidsurface covered by said layer.

A further advantage of the invention is the provision of a secondcollecting chamber communicating with the first chamber in thesupporting base and removable for the removal of the materialaccumulated therein. In this description chamber has to be understood asincluding but not limited to an open or boxed in space and/or channelsextending through the base of a brake pad and/or through the brake pad,such as but not limited to the friction material attached to the base.

Thanks to such a second chamber, a solution is provided that allowseffectively collecting the powders produced due to the wear of thefriction material in order to allow the disposal and possibly therecycling of the same powders, for instance for manufacturing new brakepads.

Advantageously, the collecting device according to the invention allowsfurther reducing dispersion of the powders produced due to the wear ofthe pad through a mechanical action. Moreover, thanks to a removableinternal lining of the collecting device, powder collectionadvantageously takes place effectively and by using means with limitedcost. Such liner can be provided in at least one chamber or severalchambers, if available.

A further, but not the last advantage of the invention is the provisionof magnetic field inside at least one chamber, or in both or allchambers when multiple chambers are provided, which fields are capableof exerting a magnetic attracting force on the particles of materialproduced due to the wear of the friction layer and the brake disk.

The brake pad according to the invention can be advantageouslymanufactured with limited modifications to the structure of theconventional pads.

A further advantage of the invention is moreover the possibility ofhousing the brake pad according to the invention within the existingbrake assemblies, without need to modify them.

In an aspect a brake pad can be defined by a supporting base with whicha layer of friction material is associated. A wall of said supportingbase having associated therewith the layer of friction material ispassed through by at least one channel communicating with a chamber,defined in correspondence of the supporting base, for collecting thepowders produced due to the wear of the friction material.

In another aspect a disk brake assembly of this disclosure can compriseat least one caliper arranged to house at least one brake pad. The atleast one brake pad can be a brake pad as claimed in any one of theclaims.

In another aspect a brake assembly, which can be as defined here above,can have associated therewith a collecting device comprising a firstbody, preferably arc-shaped, with a box structure. A hollow intended toreceive a complementary member made of a material capable of retainingthe powders can be provided within at least part of the collectingdevice.

In an other aspect a method of this disclosure can comprise collectingpowders generated by or coming from a brake pad of a vehicle brakesystem, comprising the step of providing at least one chamber associatedwith a brake pad, wherein a magnetic field is generated in or for saidchamber, attracting powder resulting from friction on the brake pad andcollecting said powder inside said at least one chamber.

Preferably at least one liner is used in or for said at least onechamber, for retaining powder inside said chamber.

BRIEF DESCRIPTION OF THE FIGURES

A description of embodiments of the invention, given only by way of nonlimiting examples, will be provided hereinafter with reference to theaccompanying Figures, in which:

FIG. 1 is a front view of the brake pad according to an embodiment ofthe invention;

FIG. 2 is a schematic cross-sectional view taken along line II-II inFIG. 1,

FIG. 3 is an enlarged view of a detail of FIG. 2:

FIG. 4 is an exploded view of the collecting member according to anembodiment;

FIG. 5 is a cross-sectional view of the collecting member according toan embodiment;

FIG. 6 is an overall view of a disk brake assembly incorporating thecollecting member according to an embodiment;

FIG. 7 discloses in partial cross section a brake pad with collectingchambers;

FIG. 8 discloses a brake arrangement seen from a top view, partially incross section;

FIG. 9A-B show a brake pad in opposite side views respectively;

FIG. 9C-D show a brake pad in perspective views according to anembodiment;

FIG. 10A-G in different steps the assembly of a brake system accordingto an embodiment, from the engine side; and

FIG. 11A-G in different steps the assembly of a brake system accordingto an embodiment, from the wheel side.

DESCRIPTION OF PREFERRED EMBODIMENT

In this description the same or similar elements in differentembodiments will be indicated with the same or similar reference signs.The figures are schematically only and should not be construed aslimiting the scope of protection as defined by the claims and the fulldisclosure. All parts and elements of the disclosed embodiments areconsidered to have been disclosed in combination as well asindividually. Any combination of parts and/or elements of the disclosedembodiments are also considered to have been disclosed in all possibleother combinations and permutations.

In this description brake pad has to be understood as meaning at leastbut not limited to a combination of elements comprising a base and atleast one pad of friction material attached thereto or an integral partthereof. In known brake systems using brake pads commonly at least twosuch brake pads are used for each wheel, at least one to each side of abrake disc to which the respective wheel is attached. In some of thefollowing drawings only one of such brake pads is disclosed, by way ofexample. Similar or identical brake pads can be used on one or on bothof said opposite sides of the brake disc.

In this description references a side view or top view of a pad orarrangement will be with reference to a position as defined by a vehiclein a normal driving position, unless otherwise defined. For discussionof the individual parts such as but not limited to the caliper of abraking system and the arrangement as such top is to be understood,unless otherwise specified, as meaning a side of the caliper facingradially outward with respect to a center of a brake disc with respectto which it is mounted, i.e. with respect to the center axis of rotationof a wheel normally mounted to or associated with said brake disc.Normal direction of rotation of a brake disc is to be understood as adirection of rotation which will occur when the vehicle moves in aforward direction, straight or in a curve or at least a direction ofmovement in which the vehicle is or will be predominantly move whensupported by at least said wheel. Engine side of a brake system has tobe understood as meaning a side facing inward with respect to thevehicle, i.e. towards a center of the vehicle, wheel side is to beunderstood as the opposite, outward facing side, i.e. the side to whichthe wheel is associated.

In this description powder or similar indications has to be understoodas at least encompassing powder, such as but not limited to particlesresulting from brake action of a brake arrangement, falling for examplein Particle Matter (PM) classes PM10, PM5 and/or PM2.5, materialsincluding but not limited to the materials as disclosed in theintroduction to the specification, for example but not limited toparticles or materials including particles at least partly attracted bymagnetic fields. Definitions and descriptions, as well as norms forEurope of Particle Matter (PM) can be found for example in the EuropeanDirective Air 2008/50/EG.

With reference to FIGS. 1 to 3, the brake pad according to theinvention, which has been generally denoted by reference numeral 11,comprises a supporting base 13, made for instance of metal, in or atwhich a first collecting chamber 17 a can be defined. Moreover, base 13has associated therewith, in conventional manner, an external layer 15of friction material intended to slow the rotation of disk DS, of whichthe prevailing rotation direction is shown by arrow “F”. According to apreferred embodiment of the invention, layer 15 of friction material,adhering to wall 19 of supporting base 13, is passed through by at leastone channel 21 communicating with the first collecting chamber 17 athrough a corresponding channel 23 formed in wall 19 of supporting base13.

Said channels 21 and/or 23 can be either perpendicular to the surface ofsupporting base 13 or inclined, and/or can include one or more bends orbe straight. The channels 21 and/or 23 can extends partly or entirelyalong the surface of the supporting base 13.

Preferably, according to according to an embodiment of the invention,layer 15 of friction material and, correspondingly, wall 19, include aplurality, for instance between 2 and 100, for example between 10 and 50such channels, such as but not limited to about a dozen, of saidchannels 21 and 23, regularly or irregularly distributed over thesurface of layer 15.

Always in accordance with an embodiment of the invention, at least onedevice 25 capable of generating a magnetic field can be arranged insideor for the first chamber 17 a. In the latter case such device 25 can beprovided outside the chamber 17 a and/or in a wall of said chamber 17 a.Multiple devices 25 for generating a magnetic field can be provided forand/or inside the relevant chamber 17 a.

Moreover, always in accordance with an embodiment of the invention, abrake pad 11 or arrangement, especially but not limited to a supportingbase 13, can optionally include a collecting reservoir 27, which ispreferably removable. In the collecting reservoir 27 a correspondingsecond collecting chamber 17 b can be defined.

In at least one of the first and second chamber 17 a, 17 b a liner 70can be provided, which liner can be made of a material that can captureat least part of the powder generated by or released form the frictionmaterial during friction between the material 15 and a brake disc DS.The liner can for example be made partially or entirely of a disposablematerial, such as but not limited to cellulose based material,recyclable material, biodegradable material and/or cleanable material.The liner 70 can preferably be removed from the or each relevant chamber17 a, 17 b together with powder PW attached thereto, and can be replacedby a new or at least rejuvenated or emptied and/or cleaned liner 70. InFIG. 3 such liner 70 is shown for the second chamber 17 b. Similarly, aliner can be provided in the first chamber 17 a, whereas a combinedliner 70 can be provided for both chambers 17 a, b. In another or thesame embodiment the at least one chamber 17 a, 17 b can be emptied inanother way, and for example regularly or at least once prior toreplacing the brake pad 11 as such, for example when its legal ortechnical life span is reached or surpassed.

In the example illustrated in FIGS. 1-3, collecting reservoir 27 isassociated with wall 29 of supporting base 13, opposed and substantiallyparallel to wall 19, in correspondence of a threaded bore 31. Accordingto such an arrangement, reservoir 27 therefore has a substantiallycylindrical shape with an open first base 33 and a closed opposite base35, and it is externally threaded at least in correspondence of its edge37 surrounding open base 33. Preferably, reservoir 27 houses, inside thesecond chamber 17 b, for instance on the bottom in correspondence ofclosed base 35, at least one device 25 capable of generating a magneticfield. Always in accordance with an embodiment of the invention, atleast one such device 25 capable of generating a magnetic field can bearranged inside or for the second chamber 17 b. In the latter case suchdevice 25 can be provided outside the chamber 17 b and/or in a wall ofsaid chamber 17 b. Multiple devices 25 for generating a magnetic fieldcan be provided for and/or inside the relevant chamber 17 b.

Such devices 25 can be for instance permanent magnets or electro-magnetsand, in the latter case, they are powered for instance by the electriccircuit of the vehicle on which the brake pad is mounted. One suchdevice can for example be suitable for use at relatively hightemperatures, for example up to or above about 100 degrees Celsius, andcould have for example a grade 35, which can be understood as a magnethaving a maximum energy product of 35 MGOe (35 Mega Gauss Oersted),which is only disclosed herein by way of example and should by no meansbe understood as limiting the scope in any way.

If such devices 25 and a liner 70 are provided in at least one of thechambers 17 a, 17 b, preferably the liner 70 separates, during use, thedevices from the powders entering into the relevant chamber 17 a, 17 b.Thus contact between the powders and the devices 25 can be limited oreven prevented.

Preferably, in accordance with an embodiment of the invention,supporting base 13 includes a portion 13 without friction material, andat least one slot or a mesh 41 defining a corresponding channelcommunicating with collecting chamber 17 a is defined in correspondencewith such portion.

In embodiments having a second chamber 17 b and a first chamber 17 a,the first chamber 17 a can be formed by an open space between thechannels 21, 23, 41 and the second channel 17 b. Powder can be forcedinto at least one of the chambers 17 a, 17 b through the channels 21,23, 41 at least partly by powder following said powder entering thechannels 21, 23, 41, and/or be pulled into said at least one chamber atleast partly be said at least one magnetic field inside at least one ofsaid chambers 17 a, 17 b. Rotational movement of the disc DS along thefriction material 15 and thus passed the channels 21, 23, 41 can alsoadd to the movement of the powder into the channels 21, 23, 41.

In accordance with an embodiment of the invention, pad 11 may includechannels 21 and 23 passing through layer 15 and wall 19, respectively,and lack slot 41, or it may lack channels 21, 23 and include said slot41 on the portion lacking the friction material, or yet it may includeboth channel 21 passing through the friction material and channel 23passing through wall 19, and slot 41.

By the provision of channels 21, 23 and/or of slot 41, the powderproduced during braking, that is during contact between layer 15 offriction material and disk DS, is directed into collecting chamber 17 a.Moreover, since such powders generally are rich in ferrous materials,they are advantageously attracted by the magnetic fields produced bydevices 25.

Advantageously, in accordance with an embodiment of the invention, slot41 is arranged downstream layer 15 of friction material in theprevailing rotation direction of disk DS shown by arrow “F”. Whenchamber 17 a and/or chamber 17 b is at least partly full, the powder canbe removed and possibly sucked out, for example by removing reservoir27. However, in a variant embodiment of the invention, the reservoir canbe replaced by a plug.

The transversal thickness of brake pad 11, which is the sum of thethicknesses of supporting base 13 and layer 15 of friction material, maybe adjusted by taking into account the need to house pad 11 within theexisting brake assemblies. Consequently, in order a chamber 17 a, b witha sufficiently great collecting volume can be defined, it might benecessary to increase the thickness of supporting base 13 to the expenseof the thickness of layer 15 of friction material.

Brake systems 81 of the relevant type, comprising at least one brake padcomprise normally a caliper 83 comprising hydraulic cylinders or suchactuators to press the or each brake pad 13 against the brake disc DS inorder to provide sufficient friction there between for reducing thespeed of the vehicle associated i.e. equipped therewith. Calipers 83usually can have an open top or opening 72 in the top, between bridges71 connecting both sides of a caliper 83, through which the disc DS canbe seen between the brake pads 11 on either side thereof. Through thisopening 72 cooling of the disc DS and/or brake pads 11 can be obtained.In embodiments of the invention, for example as shown in FIG. 8, atleast one device 25 for generating a magnetic field can be provided inor near said opening 72 for attracting powder from the friction material15 and/or the disc DS entering said opening 72. The device 25 can beprovided on a relatively open structure 73 extending into and/or acrossand/or over said opening 72, such as a netting, preferably a metalnetting or trellis work or other structure allowing air to pass, suchthat heat dissipation is still possible because the opening 72 is notclosed off by said device 25 and/or supporting structure 73. Thestructure 73 and/or the device 25 can retain the powder until it isremoved by a user or the like in environmentally friendly manner, suchas for example for environmentally acceptable disposal or reuse of thepowder.

Turning now to FIGS. 4 and 5, there is shown a collecting device,generally denoted by reference numeral 61, which can be optionallyassociated with the caliper holder where brake pad 11 is mounted, inorder to form or increase the capacity of powder retention.

Said collecting device comprises a first, preferably arc-shaped body 63with a box structure, made for instance of metal or plastics, where ahollow 65 is defined that is intended to receive a complementary member67 made of a material capable of retaining the powders, in particularfine powders, for instance a cellulose-based material. Moreover, saidbody 63 can advantageously be made integral with the caliper holderwhere brake pad 11 is mounted. The complementary member 67 can be aliner similar to and/or made of a similar material as the liners 70 asdisclosed in reference to the chambers 17 a and 17 b.

A collecting device 61 of FIG. 4 or 5 can be used in combination with anarrangement as disclosed in FIGS. 1-3 or with a known brake arrangement,for example but not limited to arrangements as described in theintroduction to the specification.

Always in accordance with an embodiment of the invention, collectingdevice 61 may internally and/or externally incorporate devices 25capable of generating a magnetic field, which are preferably locatedbetween member 67 and the wall of cavity 65.

In accordance with an embodiment of the invention, member 67 ispreferably removable and thus it can be replaced, for example when it isat least partly full or worn. Moreover, said member 67 can be fastenedinside cavity 65 by known means, such as Velcro, press studs oradhesive.

Turning to FIG. 6, there is shown a brake assembly, generally denoted byreference numeral 81, which is equipped with calipers 83 where a pair ofpads 11 according to an embodiment of the invention is housed.

Said brake assembly is associated with a brake disk DS and furtherincludes a collecting device 61 located downstream calipers 83 withrespect to the preferred rotation direction of disk DS shown by arrow“F”.

In embodiments shown the caliper 83 has two sides, each housing at leasta brake pad 11, and on at least one side at least one hydraulic cylinderfor actuating the brake pads 11. The two sides are connected by spacedapart bridge elements 71, such that the opening 72 is formed, at a topside and at least partly in said sides. At least one second chamber 17 bor at least part of the relevant reservoir 27 can extend at least partlyinto said opening 72, preferably to a side of the caliper 83. Thus moreoptimal use is made of the available space in the brake system.

FIG. 7 shows, partly in cross section, a pad 11 in an alternativeembodiment. In this embodiment the base 13 has a wall 19 with a rim 19Adefining a recessed area 17. A wall 29 comprising a reservoir 27 isprovided, which wall 29 closes off the recessed area 17, thus forming afirst chamber 17 a. The reservoir 27 again defines a second chamber 17b. The wall 29 is provided with wing elements 74 which are folded over aside of the rim 19A and partly over wall 19 for attaching the wall 29 tothe base 13. The reservoir 27 can be integral with the wall 29, and canhave any desired shape or dimension. In another embodiment the reservoircan be provided as a separate element, for example as disclosed in FIGS.1-3. A liner 70 can be provided but can also be formed differently orcan be omitted.

FIG. 8 shows in top view a brake system or assembly, in an embodimentcomprising both chambers 17 a, b and collecting device 61. As indicatedbefore, a brake system of the present disclosure could also onlycomprise one or two of said chambers 17 a, b and/or said collectingdevice 61, in any combination, or more chambers. Openings or channels21, 23, 41 could also extend at least in part or all directly into thecollecting device 61.

In the brake system as shown in FIG. 8 the caliper 83 comprises a firstside 84, for example the engine side, and an opposite second side 85,for example the wheel side. The caliper 83 will be attached to a vehiclein a known manner, preferably at an engine side. The first and secondside 84, 85 are connected by and preferably made integral with bridges71, in a known manner. The caliper 83 can be a standard type for therespective vehicle. The first side 83 comprises a chamber 86 having forexample a cylindrical shape, which can form part of a main or additionalbrake cylinder system. A hydraulic or brake fluid supply line 87 canextend into said chamber 86, in a known manner. Within said chamber 86 abrake piston 89 is provided, in a known manner. The piston 89 is hollowand for example cylindrical and movably sealed against said chamber 86by a seal system or arrangement 88, such that the piston can de factoform a piston of the brake piston cylinder arrangement, such that whenbrake fluid or hydraulic fluid is supplied to said chamber 86, thepiston is actuated. The reservoir 27 extends into the hollow piston 89,which piston abuts the wall 29 of the pad 11 and thus upon saidactuating of the piston 89 the pad 11 is moved towards the disc DSrelative to the caliper side 83, such that the brake is activated andthe disc DS is prevented from or at least restrained in possiblerotation, thus braking the vehicle. Preferably the reservoir 27 fitsspaciously within said hollow reservoir, such that it can be placed andremoved relatively easily.

On the opposite second side 85 the reservoir 27 extends through theopening 72 to the relevant side of the caliper 83, and can be part of aso called passive brake pad 11, meaning that when the brake isactivated, relative movement of the caliper 83 in side direction S,resulting from said fluid entering said chamber 86, will force the pad11 at the second side 85 against the disc DS too. Thus optimal brakingwill be obtained.

In the embodiment of FIG. 8 the device 61 can be provided with twobodies 63, one to each side of the disc DS, connected to the respectivesides 84, 85 of the caliper 83, extending substantially alongside partof the disc DS, in the direction F downstream of the caliper 83. Eachbody 63 can be provided as a bent strip, forming a loop. The body orstrip can be made of any suitable material. An attachment means, such asfriction material, Velcro, glue or any other suitable means can beprovided on the strip, for attaching, preferably releasably, a member 67to said bodies 63. In the same or other embodiments the member 63 can bepress fit or form retained within or on said bodies. In the embodimentshown the member 67 is in top view substantially C-shaped, such that itextends from one side 84 around the peripheral edge of the disc DS tothe opposite second side 85. The member is hollow on the inside, i.e.the side facing the disc DS, and has an outer shape such that it fits,preferably snugly, within the loops formed by the bodies 63, to beattached thereto or at least held partly in position by said bodies,especially but not necessarily by the attachment means. The sides of themember 67 facing the disc DS can extend at a short distance from theadjacent surfaces 90 of the disc DS, for example in the order ofmillimeters or less, such that preferably no contact between the memberand the disc will occur, whereas as little as possible of the powder canpass between the member and the disc, at least at the downstream endthereof, facing away from the caliper 83. The member 67 can be made ofthe same or different material as the liner 70 as discussed before. Themember 67 can form one or more chambers 67A, on opposite sides 90 of thedisc DS. If there are separate members 67 on said opposite sides, eachmember will provide at least one such chamber 67A. Covers 91 can beprovided on either side 84, 85, over the respective parts of the member67, especially within the bodies 63. In and/or on the covers 91 devices25 for generating a magnetic field can be provided, for generating suchmagnetic field with respect to and preferably in the chamber or chambers92 formed within member 67 facing and open towards the disc DS. Powderwill then be adhered at least partly to said member, at least partlyattracted by the magnetic field.

Devices 25 for generating magnetic fields can be chosen dependent on forexample their use, the size of the chambers 17 a, 17 b and/or device 61,the size and type of vehicle, the materials used for the frictionmaterial and/or the brake disc DS and other considerations, which willbe directly clear to the skilled person.

FIG. 9 shows a brake pad 11 in four different views. FIG. 9A shows thefriction material 15 side, clearly showing entrances of channels 21extending through the friction material 15. At opposite sides bracketelements 92 are provided, forming part of or being attached to the basewall 19 of the pad 11 or at least of or to the base 13. Channels 21 orat least the openings thereof can be of different size and/or shape, orcan be identical, and can be regularly or irregularly spaced. Thenumber, sizes and patterns of the channels can be chosen by a skilledperson, based on factors defined by the specific application.

In FIG. 9B the opposite side is shown, which in use extends at a sidefacing away from the disc DS. This shows the wall 19 with the openings23 in communication with the channels 21. FIG. 9B clearly shows therecessed area 17 within the rim 19A.

FIG. 9C shows in perspective view the pad 11 with the wall 29 comprisingthe reservoir 27 which includes the second chamber 17b, mounted over thewall 19 and especially against at least part of the rim 19A. Wings 74are folded around part of the rim and wall 19, 19A for attaching thewall 29 with the reservoir 27. In FIG. 9D this is also shown in the pad11, from a different angle. As can be seen the reservoir 27 can have aheight H extending from the wall 29, which can be greater than thethickness t of the friction material 15. The brackets 92 can be used forexample for guiding the pads 11, for support and for limiting movementof the pad 11.

FIG. 10A-10G show in steps the configuration of a brake assembly 81 ofthe disclosure, in a combined embodiment of chambers 17 a, 17 b andcollecting device 61. In other embodiment one or more of these can beleft out or combined differently.

FIG. 10A shows a caliper bracket 93, from one side 84, for example anengine side, showing a body 63 attached to one end thereof. The bracket93 is substantially C-shaped and is in a known manner formed andprovided with mounting openings 94 or such means for mounting thebracket to the further vehicle and/or for mounting the further part orparts of the brake system, especially of the caliper 83. In FIG. 10B thebracket 93 is shown, mounted over part of a brake disc DS. The normaldirection of rotation F is shown, indicating that the body or bodies 63is or are provided down stream from the caliper bracket 93, and, as willbe discussed, of the caliper 83. The bracket 93 can be an integral partof the caliper 83 or can be provided separately, as is shown in FIGS. 10and 11. The body or bodies 63 can also be an integral part of thebracket 93 and/or of the caliper 83.

In FIG. 10C a pad 11 is shown in position in and/or on the bracket 93,in which the reservoir 27 and the wall 29 are clearly visible, thereservoir extending substantially away from the disc DS. A magnet orsuch magnetic field generating device 25 may be comprised in or on thereservoir 27. FIG. 10D shows the caliper 83 mounted on the caliperbracket 93, attached by fasteners in openings 94. The reservoir 27 issubstantially contained in the piston 89 of the caliper 83, such thatthe piston engages the wall 29. Obviously the piston can additionally orinstead thereof engage the reservoir 27 for pressing the pad 11 againstthe disc DS.

In FIG. 10E a cover 91 is shown, form a side, to be referred to as innerside 94 facing the disc DS when properly mounted to the body 63. In thecover 91 a number of magnets or such devices 25 for generating a powderattracting field, such as a magnetic field is provided, at said innerside 94. They could also all or some be provided partly or entirely onthe opposite, outer side of the cover or on the member 67. In FIG. 1OFthe member 67 is shown, held in position at least partly in the body 63,the chamber 67A of the member 67 facing the disc DS. The member 67 canfor example be placed by pulling the bodies 63 slightly apart andinserting the member there between from and over the radial side of thedisc DS and then releasing the bodies 63 again, which will then encloseor at least retain the member 67.

In FIG. 10G the cover 91 is provided over the relevant side of themember 67, thus positioning the devices 25.

FIG. 11A-G show in steps similar to and partly coinciding with the stepsas discussed with respect to FIG. 10A-G, but seen from the opposite side85, in this embodiment from the wheel side. In FIG. 11A the wheel sideof the bracket 93 with the body 63 is shown, shown the two loops of thebody 63, connected to the bracket 93. In FIG. 10B the bracket 93 isshown, mounted partly over the disc DS, showing one of the loops of thebody 63 at the wheel side of the disc DS. In FIG. 11C the relevant pad11 is shown, in position. In this embodiment the reservoir 27 of thisside can be slightly oblong shaped, to fit within the opening 72 of thecaliper 83, as is shown in FIG. 11D.

In FIG. 11E again a cover 91 is shown, form a side, to be referred to asinner side 94, facing the disc DS when properly mounted to the body 63.In the cover 91 a number of magnets or such devices 25 for generating apowder attracting field, such as a magnetic field is provided, at saidinner side 94. They could also all or some be provided partly orentirely on the opposite, outer side of the cover or on the member 67.In FIG. 11F the member 67 is shown, held in position at least partly inthe body 63, the chamber 67A of said member 63 facing the disc DS. InFIG. 11G the cover 91 is shown, placed over the relevant part of themember 67.

Tests have been performed with pads 11 and a brake arrangement 81 of anembodiment of the present invention, which have shown that a highpercentage of the powder or particles generated by braking with the padscan be collected into the chambers 17, 17 a and/or 67 a and/or by anydevice 25 provided in the arrangement 81, in combination. In tests abrake arrangement 81 as shown in FIGS. 9-11 was used, on a regular testbank. Before mounting the arrangement 81 the weight of the frictionmaterials 15 of the individual pads 11 was established, providing astarting weight. Then the disc DS was driven and braked regularly,providing friction and thus wear of the friction material 15 of the pads11 and of the disc DS. After a desired number of revolutions of the discand a desired number of brake actions, the arrangement was dismantledand the weight of the remaining friction materials 15 of the pads wasestablished, providing an end weight. Also the weight of the totalamount of powder collected inside the chambers 17 a, 17 b and 67 a wasestablished. The difference between the start weight and the end weightof the friction material 15 of the pads was defined as the frictionmaterial consumption. The weight of the powder collected was comparedwith the material consumption, showing that a percentage of more than90% of the friction material consumption could be collected in thisprototype of a brake system 81 according to this disclosure. Fromcomparative tests it has been shown that even more powder could becollected in said chambers 17 a and 17 b and 67 a, including materialresulting from wear of the disc DS. This shows that indeed use of abrake assembly 81 and/or brake pads 11 and/or a collecting device 61according to an embodiment of the present invention can lead to amassive reduction of powder coming from vehicle braking systems andarrangements entering into the environment in an uncontrolled manner.

From tests it has been found that differences in friction and/orfriction matter consumption can occur between pads 11 in the samecaliper, for example due to difference forces exerted thereon. Withoutwanting to be bound to any theory, one explanation thereof appears to bethe position of the brake piston to one side of the used caliper. In thetests the consumption of friction material of the pad 11 at the side ofthe brake cylinder-piston was higher than the consumption of frictionmaterial 15 of the pad 11 at the opposite side. To accommodate for thisdifference the pad 11 at the side of the brake cylinder-piston could forexample be provided with a set of channels 21, 23, 41 which differ fromthe set of channels and/or openings of the other pad, for example alarger number of channels and/or openings, bigger channels and/oropenings and/or a different position of such channels and/or openings onthe side of the brake cylinder-piston than on the opposite side, or viceversa. As indicated before, optimizing can easily be done within thescope of this disclosure based on for example the vehicle type,materials used, brake forces available, pad sizes and dimensions and thelike criteria.

Providing removable and/or replaceable liners 70 an/or members 67 asdisclosed here above can additionally or separately provide for easymaintenance of a brake arrangement, reduction or elimination ofinconvenience or risk for users, and for easy control of effectivenessof such arrangement. Such liners 70 could also be used in other brakearrangements, such as but not limited to arrangement as disclosed in theintroduction to the specification. Liners 70 could be magneticallyand/or statically charged, for enhancing adherence of powder to theliner.

A brake pad 11 and/or brake arrangement 81 can for example be used asfollows, for collecting powders generated by the brake pad of a vehiclebrake system. In or at at least one chamber (17 a, 17 b, 67 a)associated with a brake pad (11) preferably a magnetic field isgenerated, in or for said chamber (17 a, 17 b, 67 a), attracting powderresulting from friction on the brake pad (11). Said powder is retainedwithin said at least one chamber (17 a, 17 b, 67 a). The chamber (17 a,17 b, 67 a) can be provided with a liner (70) or have a wall materialsuitable for the powder to adhere to. After a while, for example arelevant number of miles, hours or brake actions, during check ups ofthe vehicle or at regular or irregular intervals the chambers (17 a, 17b, 67 a) can be inspected and for example be cleaned out, emptied and/orprovided with at least one new liner (70) or member (67) or completedevice (61). When the brake pads (11) have outlived their technical lifeexpectancy they may also be changed, in a normal manner.

An embodiment of the present invention is by no means limited to thegeneral and specific disclosures of embodiments as shown and/ordescribed here above by way of example only. Combinations of partsthereof and alternatives thereto are also considered to have beendisclosed and to fall within the scope of this disclosure. Furtheramendments and variations are possible, for example but not limited toembodiments wherein the member 67 and the cover or at least one cover 91are combined, wherein the device 61 is exchangeable in its entirety foranother such device 61, and can for example be disposed, replaced,recycled and/or cleaned in its entirety. Such device can then forexample be clipped, screwed or otherwise be attached to the caliper 83or caliper bracket 93 or otherwise held in position relative to the discDS. A device 61 could also or alternatively be provided upstream of thecaliper 83. Additional means could be provided for sucking and/orotherwise forcing powder into at least one of the chambers, such as butnot limited to suction means, for example means for creating a subatmospheric pressure inside at least one of the chambers (17 a, 17 b, 67a), preferably at least during rotation of the disc DS relative to thecaliper, such as but not limited to a vacuum pump, or by creating an airstream, for example by ventury action, using a liner 70, 67 or suchelement within the chamber (17 a, 17 b, 67 a) through which the airstream can pass but which acts as a filter for the powder. Means can beprovided for providing an indication of the filling of one, more or allof the chambers (17 a, 17 b, 67 a), for example electronic means,indicative for the moment the chambers need to be emptied or at leastinspected and/or liners and/or members need to be taken care of, forexample replaced, emptied and/or cleaned.

What is claimed:
 1. A brake dust collecting device for connection with abrake pad assembly, the brake dust collecting device comprising: an arcshaped body configured to connect with the brake pad assembly, the arcshaped body comprising: a member defining a chamber, the member havingat least one opening for communication with the brake pad assembly, thechamber defined for collecting powders produced due to the wear offriction material of the brake pad assembly.
 2. The brake dustcollecting device of claim 1, wherein the arc shaped body is configuredto removably connect with the brake pad assembly.
 3. The brake dustcollecting device of claim 1, the arc shaped body further comprising: aliner internal to the member chamber and configured to collect thepowders.
 4. The brake dust collecting device of claim 3, wherein theliner is removable for collection of the powders.
 5. The brake dustcollecting device of claim 1, the arc shaped body further comprising: amagnet adjacent the chamber and configured to attract the powders. 6.The brake dust collecting device of claim 5, wherein the magnet isexterior of the member.
 7. The brake dust collecting device of claim 5,wherein the magnet is a part of the member.
 8. The brake dust collectingdevice of claim 5, wherein the magnet is at least one of a permanentmagnet or an electro-magnet.
 9. The brake dust collecting device ofclaim 3, wherein the liner is at least partially made of a disposablematerial.
 10. The brake dust collecting device of claim 9, wherein theliner is at least partially made of at least one of a cellulose basedmaterial, a recyclable material, a biodegradable material, or acleanable material.
 11. The brake dust collecting device of claim 1,wherein the arc shaped body further comprises: a first body and a secondbody, each of the first and second bodies configured to be positioned onopposite sides of a disk brake of the brake pad assembly; and aconnecting member connecting the first body and the second body.
 12. Thebrake dust collecting device of claim 11, wherein the connecting memberextends from one side of the disk brake to the other side to connect thefirst body and the second body.
 13. A method of collecting powdersgenerated by a brake pad of a vehicle brake system, comprising the stepof providing at least one chamber associated with a brake pad assembly,wherein a magnetic field is generated in or for the at least onechamber, attracting powder resulting from friction on the brake pad andcollecting said powder inside said at least one chamber.
 14. The methodaccording to claim 13, wherein a liner is provided in or for said atleast one chamber, preferably made of a material capable of retainingthe powders inside said at least one chamber.
 15. The method accordingto claim 13, wherein the at least one chamber is emptied before thefriction material of said brake pad is worn out and the pad is replacedby another brake pad, wherein preferably a liner or member is removedfrom the at least one chamber, together with the powder and is replacedby another liner and/or member.
 16. A brake assembly comprising acaliper and a brake disc, wherein at least one brake pad is mounted inthe caliper for engaging a side of the brake disc, which disk brake padcomprises a supporting base with which a layer of friction material isassociated, wherein at least one chamber is provided for collectingpowders produced due to the wear of the friction material, wherein thechamber is provided in a body extending from the at least one brake pad,seen in a direction of rotation of the brake disc.
 17. The brakeassembly according to claim 16, wherein the chamber is provided in amember positioned in or provided on said body.
 18. The brake assemblyaccording to claim 16, wherein the body is provided extending over atleast a peripheral edge of the brake disc and extending at oppositesides of said brake disc.
 19. The brake assembly according to claim 16,wherein the body is provided extending over at least a peripheral edgeof the brake disc and extending at opposite sides of said brake disc,wherein the chamber is provided extending also over at least aperipheral edge of the brake disc and extending at opposite sides ofsaid brake disc.
 20. The brake assembly according to claim 16, whereinat least at least one liner is provided in the chamber and/or in acollecting reservoir associated therewith, which liner covers means forgenerating a magnetic field in said chamber and/or said collectingreservoir.
 21. The brake assembly according to claim 16, wherein meansfor generating a magnetic field are provided in or for said chamber. 22.The brake assembly according to claim 16, wherein a liner is provided inthe at least one chamber and/or reservoir, which liner is replaceablefor another liner.
 23. The brake dust collecting device of claim 1,wherein the arc shaped body is integrally connected with the brake padassembly.